Phase composition, structure, corrosion and radiation resistance of synthesized Ca₁₀(PO₄)₆F₂ and Ca₉Sr(PO₄)₆F₂ fluorapatites

Abstract

The effect of electron irradiation (E up to 10 MeV) on the phase composition, structure, and corrosion resistance of synthesized fluorapatite was investigated in the study. Powders of calcium Ca₁₀(PO₄)₆F₂ and strontium-containing Ca₉Sr(PO₄)₆F₂ fluorapatites were synthesized by the method of co-precipitation from the solutions of the initial components. The samples of fluorapatite with a maximum value of the relative density (90-92 %) were produced by sintering in air at a temperature of 1250 °C for 6 h. The secondary phase of tricalcium phosphate α-Ca₃(PO₄)₂ in the resulting samples was observed. Increasing the heat treatment time up to 9 h leads to a disorder in the structure of the fluorapatite. XRD analysis of glass-ceramic fluorapatite samples after electron irradiation process has shown the lines of fluorapatite and &qout;halo&qout; in the diffractogram, which indicates amorphization of fluorapatite samples. It has been established that electron irradiation to absorbed dose of 108 Gy does not significantly affect the corrosion resistance of the obtained fluorapatite samples.